coronal hole


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coronal hole

[kə′rō·nəl ‚hōl]
(astronomy)
A large-scale, apparently open structure in the solar corona, devoid of any soft x-ray emission and surrounded by diverging boundary structures.
References in periodicals archive ?
Washington, Oct 16 ( ANI ): Researchers have found evidence that magnetic waves in a polar coronal hole contain enough energy to heat the corona and that they also deposit most of their energy at sufficiently low heights for the heat to spread throughout the corona.
In the image, one coronal hole appears near the top center of the sun while another one – a polar coronal hole – is visible near the bottom of the view", space.
The aurora seen on 2013 Aug 04/05 was the result of a coronal hole high speed stream with the IMF producing a southerly Bz with a strength of -13nT.
Washington, July 20 ( ANI ): European Space Agency/NASA Solar and Heliospheric Observatory, or SOHO, captured images of a gigantic coronal hole hovering over the Sun's north pole on July 18.
The center expects quiet-to-unsettled levels on August 11 due to the expected arrival of a recurrent coronal hole high-speed stream.
For example, the flows look like coronal hole regions on the Sun, or, regions where the plasma does not exceed about 1 million degrees K and flows outwards along open field lines becoming the fast solar wind.
CORONAL-HOLE: A significantly large coronal hole rotated across the middle of the Sun to be in a position to affect Earth (Dec.
Washington, July 10 ( ANI ): Scientists at Columbia University's Astrophysics Laboratory in New York, have found evidence that magnetic waves in a polar coronal hole contain enough energy to heat the corona and deposit most of their energy at sufficiently low heights for the heat to spread throughout the corona.
By way of contrast, December was a very quiet month for solar activity, the Kp only rising to 4 on Dec 17 as a result of a coronal hole high speed stream.
I think that as Ulysses heads back down to lower latitudes, the sun is getting quieter and quieter as the large polar coronal hole that emits the high-speed stable solar wind reopens behind us," said McComas.
WASHINGTON (CyHAN)- A significantly large coronal hole rotated across the middle of the Sun to be in a position to affect Earth (Dec.
This dovetails with evidence that the south pole has a large coronal hole, a source of the wind.